The goal of Core C (Biostatistics &Data Management) is to provide expert guidance and consultation in the biostatistical and data management aspects of the design, conduct, and analysis of research projects generated by the P01. Core C will provide statistical collaboration and also support the P01 's clinical research activities by designing, implementing and operating a data management system for the projects' gene therapy clinical trials. Core C will provide its services to P01 projects at every stage of the research: Prior to the initiation of studies, Core staff will consult with P01 investigators to help them select efficient designs and sample sizes that will give adequate power to address study objectives. For gene therapy clinical trials, they will establish data management systems and design case report forms that collect all required information in an unambiguous way. As studies proceed, Core staff will enter data, manage and monitor clinical trial databases, implement and execute data quality control activities, and prepare data reports. When studies are finished, the Core will conduct correct and efficient data analyses, prepare any necessary graphs and tables, assist investigators with the preparation of presentations and manuscripts, and consult on the design of subsequent research. The work of Core C will involve close integration with the efforts of all the research projects. Core C staff members have extensive experience supporting cancer research, with strong backgrounds in basic science, translational research, clinical trials, research computing, and data management. With their many years of experience in applied and methodologic statistical research, they stand ready to choose the best approaches from the pool of existing methods and to adapt or develop new methods as needed.